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Finding the Fourth Proportional to 205.68, 308.56 and 68.80

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Solution

The fourth proportional to 205.68, 308.56 and 68.80 is: 103.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    205.68 : 308.56 = 68.80 : x
  2. Step 2: Convert to fraction form
    205.68/308.56 = 68.80/x
  3. Step 3: Cross multiply
    205.68x = 308.56 × 68.80
  4. Step 4: Simplify right side
    205.68x = 21,228.93
  5. Step 5: Solve for x
    x = 21,228.93/205.68
  6. Step 6: Final answer
    x = 103.21

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.